Temperature-indicating means



July 10, 1928.

K. A. FERKEL TEMPERATURE INDICATING MEANS Filed Aug. 26, 1925 NVENTOR. jy

PATENT I OFFICE.

KARL A. FERKEL, OF LOS ANGELES, CALIFORNIA.

TEMPERAT'Q'RE-INDICATING MEANS.

Application filed August 26, 1925. Serial No. 52,623.

The object of my invention is to provide a new temperature indicatingmeans.includ ing a signal covering substance which under change oftemperature will disappear and disclose the signal element.- In mypending application, Serial Number 684,308, I have presented a coveringmatter which, under change of temperature, changes from opaqueness totransparency and thereby presents to view the signal element. Thepresent inven} tion, however, is more like a disappearing curtain forthe substance is such that the prc determined temperature will cause itto disappear and uncover the signal or warning element. Another objectof my invention is to provide in combination a plurality of similarsignal elements, covered with substances which disappear at difierenttemperatures, so that there can be successive indications as 0 thetemperature increases to warm, hot, and

danger point. These are mentioned as illustratlons, or examples, of theapplication of the invention for plural temperatures. In order to morefully explain my invention, I have illustrated its embodiment in twoslightly difierent forms on the accompanying sheet of drawings, which Iwill now describe. Figure 1 is a perspective view of one em- 7 0bodiment of my invention, capable of being attached to an article whichis subject to possible overheating, with parts broken awa Figure 2 is aface-view thereon on a smaller scale;

Figure 3 shows the invention as it might a be attached to a buss bar orelectric connectin member which might be overheated; and igure 4 showsthe invention as applied 40 to a pipe which might. form an importantpart in a system of oil treatment or distillation and subject topossible overheating. f The invention as here illustrated comprises abody member, 1, of elongated form, having 7 therein three pockets, orchambers, 2, 3 and 4, the back walls, of which are preferably made red,as indicated by the shading. Said ockets have within them the signal orwarnmg element, in the present showing, being the words Warm Hot and Daner..

a a g A covering substance is placed over these words in said pocketsand so covers them that they cannot be read. In one case, the substanceis one that disappears by decom- 5 5 position, designated 5, andammonium cyanide is mentioned as an example, this being a chemical whichdecomposes at v36 C., the products of decomposition being gases whichwill pass from the pocketior disappear and thus uncover the signalelement, which in this case is the word Warm. "The second pocket, 3, hastherein the signal or warning element Hot and the covering or curtainmatter is designated, 6, and beta ethyl chlorocarbona-te is mentioned asthe example, this being a substance which boils at 92 to 94 and leavesthe container or pocket and uncovers the signal element; Anothersubstance which might be used is iodine, this being a substance whichsublimes or changes from the solid to a gaseous state at a tem peratureof 184 C. A further substance or matter which might be used where hightemperature can be reached before thedanger point is approached is puremetallic lead, which melts at 327 C. and if this tempera t'ure should bereached, said lead curtain or cover would-melt and run oif of the signalelement so as to expose the. same and give the indication or evidencethat such high temperature had been reached; -Forpurpo'ses of thisapplication, either the iodine, or pure metallic lead, can be indicatedas a cover, 7, in pocket 4, depending on which temperature is desired tobe the predetermined temperature at which -the warning or signal shouldbe iven.

In all these cases, it is to e noted that when the predeterminedtemperature is reached, the covering substance is caused to disappearfrom the signal element and to uncover and expose said signal or warningelement. a

The device may be made with a transparent cover, as 8, over each pocket,and with attaching tears, as 9, 9, or with spring clips,

10, 10, indicated in light broken lines for the purpose of attaching thesame, to a flat object., 11, which might be a buss bar or other electricconnecting member, or to a pipe, '12, in any system in which thetemperatures reached are registered in'said pipe.

While I have shown and described certain embodiments or applications ofmy inventio'n, it is to be understood thatthese have been shown forexplanatory and illustrative purposes, and I do not limit my inventionexcept as I may be limited by the hereto appended claims.

' I claim:

having therein a plurality of di'fierent cham each of said chambersnormally hiding from view said signal element, said substances, beingcapable of changing their form so as to expose to view said signalelements. cov-' ered thereby, and requiring difl'erent tem-' peraturesto cause said change in form, whereby to indicate that one temperaturehas been reached'and another has not been reached.

2., Temperature indicating means consisting of a casing adapted to beplaced against a surface Sllb]8Ct to change of temperature, said casinghaving therein a plurality of different chambers with transparentcovers, means'back of said covers to serve as signals whenexposed toview, a substance in each of said chambers and normally covering saidsignal means, said substances each being capable of change of form toexpose said signal means to view and each requiring a difierenttemperature to effect such change, whereby said device is operable toindicate that a temperature has been reached between that required tochange one substance and that required to change another of saidsubstances.

change in temperature and having a cham-- her, a substance in saidchamber which is normally opaque and possessing-the characteristic ofchanging its form by rise in tem-peraturefrom opaqueness to gaseousform, and a signal element covered by said substance and hidden from.view while said substance remains in its opaque form and exposed to viewwhen said substance changes its form to a gaseous condition by reason ofthe rise in temperature.

4. A device specially designed to indicate change in temperatureincluding asubstance placed to hidefrom view a signal element, a signalelement, said substance releasing itself through a chemical change whena certain temperature is reached, thereby exposing said signal elementto view.

5. A device specially designed to indicate change in temperatureincluding a substance placed to hide from viewasignal element, a signalelement, said substance releasing itself through a physical change whena certain temperature is reached, thereby exposing said signal element.to view..

Signed at Los Angeles,- Los Angeles County, California, this 21st day ofAug, 1925.

- KARL A. FERKEL)

